Over the past five years, I have bought 4 dashcams from blackboxmycar, three DR750S-2CH and one DR900S-2CH. Overall, I've been very happy with the product and shipping/service.
I use the cameras as another insurance policy, just in case if there's an accident on the road and someone points a finger at me. I have the DR750S cameras installed on 2014 Subaru Outback, 2020 Honda Passport, 2018 Subaru Crosstrek. I have the DR900S camera installed on a 2020 Honda Insight (previously had installed on a 2019 VW Golf Alltrack and 2018 Ford Expedition).
Blackboxmycar is my go-to store for dashcams now. Their shipping is very fast, with immediate notification of shipping, etc. Never had a problem with fulfillment from them. I think I had one question that I sent by e-mail regarding another product; they were very responsive. Their prices are very competitive. Their support via their YouTube channel is exceptional. In fact, I learned about their products via YouTube initially. Their install videos made me feel very comfortable about diving into doing a DIY install. After having done 6 of these installs myself (I installed one of these cameras in three different cars), I feel very comfortable doing another one or trouble-shooting any issues.
Blackvue cameras are great. Honestly, I wish I had other brands to compare so that I can say that they are the best, but these things are expensive, so once I had a Blackvue camera, I wanted to get Blackvue cameras for my other cars so that all I had to do was to deal with one company for any support issues and to use one app on my phone for working with the videos, etc. The videos are very clear, with better than adequate details for getting information for any potential accidents. Thank goodness, I never had to use the videos for any insurance or legal issues, but I'm confident that if I were in an accident, I would have more than adequate video evidence. Right now, I mostly use the camera to show my wife anything I saw on the road (mostly crazy drivers or people being idiots).
One issue that I had with the DR900 camera was possibly an overheating issue. This happened only once when I had the camera installed on a 2018 Ford Expedition (this car can be a big green house during the summer months). The camera kept restarting and did not work for awhile, and this was trouble-shooted to a potentially heat-damaged SD card. I replaced the SD card and had no issues since. Subsequently I had the camera installed on the VW and the Honda with no issues.
Again, I cannot see how you can go wrong with getting the Blackvue dashcam from blackboxmycar.